Fix absolutely shameful bug that caused some reviews to not be loaded.

If a paper is in PHASE_FINAL, the old code mistook that as meaning
the paper had full reviews loaded, whether or not it did.

src/paperinfo.php

@@ -1034,7 +1034,7 @@ function phase() {
             } else {
                 $phase = self::PHASE_REVIEW;
             }
-            $this->_flags = ($phase & ~self::PHASE_MASK) | self::HAS_PHASE | ($phase << self::PHASE_SHIFT);
+            $this->_flags = ($this->_flags & ~self::PHASE_MASK) | self::HAS_PHASE | ($phase << self::PHASE_SHIFT);
         }
         return ($this->_flags & self::PHASE_MASK) >> self::PHASE_SHIFT;
     }